LONDON (AP) — Britain’s competition watchdog said Wednesday that it will investigate plans by drug maker GlaxoSmithKline PLC to pool resources with Pfizer Inc. to create a new company to develop and sell HIV medicines. The Office of Fair Trading said it will decide whether the joint venture can be considered to be a merger that will reduce competition in the UK. It also will decide whether to refer the case to the Competition Commission regulators, which have the power to block or put limits on the deal. The OFT said interested parties had until June 9 to submit their views for the first stage of consultations. GlaxoSmithKline, the world’s second largest drug maker by revenues, said last month that it plans to form a new company with Pfizer Inc. that will blend Galaxo’s portfolio of HIV drugs now on the market — some with patents approaching expiration — with New York-based Pfizer’s more robust pipeline of drugs in development. With 11 HIV medicines already on sale, the new venture would have a 19 percent market share, ranking it No. 2 behind sales leader Gilled Sciences Inc. Other competitors in the field include heavyweights Bristol-Myers Squibb Co., Abbott Laboratories, Merck & Co. and Dumont Pharmaceuticals Co.